A portable power tool, such as a hedge trimmer, typically uses a driving mechanism that transmits the power generated by an electric/battery operated motor or an internal combustion engine to a cutting assembly through a gearbox. The portable trimmer may be operated by a clutch, which in turn controls the power from the motor/engine, and thereby drives the cutting assembly through a clutch drum to perform trimming work. The cutting assembly of a portable hedge trimmer includes one or more cutting blades which may move relative to each other to perform the cutting operation.
The gearbox is lubricated by pumping one or more strokes of grease. However, over-lubrication may cause the gearbox to run slower than normal, and may also cause a leakage in the form of excess grease that flows out from the gearbox onto the cutting assembly. This may lead the cutting blades in the cutting assembly to stick tight with each other when the trimmer is not in an operational state. This may lead to operational problems, such as jamming of the clutch, during subsequent operation of the trimmer. Further, this may also lead to excessive energy consumption in battery powered tools. Moreover, this may pose problems in assembling and disassembling of the trimmer system for inspection or fixing purposes.
Thus, during operation of the trimmer, it is required to inhibit the cutting blades from sticking to each other. Therefore, there is a need for an improved portable power tool, which provides a means for preventing the flow of grease from the gearbox onto the cutting assembly.